/* Kern — optional reusable motion effects. Import with Tailwind after kern-base.css. */
:root {
  --k-motion-enter-scale: 0.96;
  --k-motion-enter-offset: 4px;
}

/* Apply when revealing a floating panel. Replays after display:none / hidden. */
@utility animate-menu-in {
  animation: k-menu-in var(--k-motion-duration-sm) var(--ease-standard);
  transform-origin: var(--k-motion-origin, top center);
  &[data-k-menu-state="closing"] {
    animation: k-menu-out var(--k-motion-duration-xs) var(--ease-standard) both;
  }
  @media (prefers-reduced-motion: reduce) {
    &, &[data-k-menu-state="closing"] { animation: none; }
  }
}

@keyframes k-menu-in {
  from {
    opacity: 0;
    transform: translateY(var(--k-motion-offset, calc(-1 * var(--k-motion-enter-offset)))) scale(var(--k-motion-enter-scale));
  }
  to { opacity: 1; transform: translateY(0) scale(1); }
}
@keyframes k-menu-out {
  from { opacity: 1; transform: translateY(0) scale(1); }
  to {
    opacity: 0;
    transform: translateY(var(--k-motion-offset, calc(-1 * var(--k-motion-enter-offset)))) scale(var(--k-motion-enter-scale));
  }
}

/* The UI file provides a static indeterminate fallback when effects are omitted. */
@layer components {
  .k-progress:not([value]) {
    animation: k-progress-indeterminate 1400ms linear infinite;
    &:dir(rtl) { animation-direction: reverse; }
    @media (prefers-reduced-motion: reduce) { animation: none; }
  }
}
@keyframes k-progress-indeterminate {
  from { background-position: -66.667% 0; }
  to { background-position: 166.667% 0; }
}

/* Reuse Tailwind's pulse; UI-only imports leave a static loading placeholder. */
@layer components {
  .k-skeleton {
    @apply animate-pulse;
    @media (prefers-reduced-motion: reduce), (forced-colors: active) { animation: none; }
  }
}

/* A straight, 1.6-second text shimmer. Without this file, text renders normally. */
@utility k-shimmer {
  @apply inline-block w-fit max-w-full;
  @supports (background-clip: text) or (-webkit-background-clip: text) {
    background-image: linear-gradient(
      90deg,
      currentColor calc(50% - (4ch + 48px) / 2),
      color-mix(in oklab, currentColor 20%, var(--k-canvas)) 50%,
      currentColor calc(50% + (4ch + 48px) / 2)
    );
    background-size: 300% 100%;
    background-repeat: no-repeat;
    background-position: 100% 0;
    background-clip: text;
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    animation: k-shimmer 1600ms linear infinite;
  }
  @media (prefers-reduced-motion: reduce), (forced-colors: active) {
    animation: none;
    background-image: none;
    -webkit-text-fill-color: currentColor;
  }
}
@utility k-shimmer-once { animation-iteration-count: 1; animation-fill-mode: forwards; }
@utility k-shimmer-none {
  animation: none;
  background-image: none;
  -webkit-text-fill-color: currentColor;
}
@keyframes k-shimmer {
  from { background-position: 100% 0; }
  to { background-position: 0% 0; }
}

/* Shared keyboard-focus entrance. The final outline comes from base/component styles. */
@layer base {
  :focus-visible {
    animation: k-focus-in var(--k-motion-duration-xs) var(--ease-standard);
  }
  @media (prefers-reduced-motion: reduce) {
    :focus-visible { animation: none; }
  }
}

/* Hidden native inputs paint their focus ring on a visible sibling. */
@layer components {
  .k-input-group:has(> .k-input:focus-visible),
  .k-checkbox > input:focus-visible + .k-checkbox-control,
  .k-switch > input:focus-visible + .k-switch-track,
  .k-segmented-control input:focus-visible + span {
    animation: k-focus-in var(--k-motion-duration-xs) var(--ease-standard);
  }
  @media (prefers-reduced-motion: reduce) {
    .k-input-group:has(> .k-input:focus-visible),
    .k-checkbox > input:focus-visible + .k-checkbox-control,
    .k-switch > input:focus-visible + .k-switch-track,
    .k-segmented-control input:focus-visible + span { animation: none; }
  }
}

@keyframes k-focus-in {
  from { outline-color: color-mix(in srgb, var(--color-focus) 0%, transparent); outline-offset: 0; }
  to { outline-color: var(--color-focus); }
}

/* Tooltip motion follows the final placement, including viewport flips. */
@utility animate-tooltip {
  --k-tooltip-motion-x: 0px;
  --k-tooltip-motion-y: 0px;
  animation: k-tooltip-in var(--k-motion-duration-base) var(--ease-standard) both;
  transform-origin: var(--k-motion-origin, center);
  &[data-k-side="top"] { --k-tooltip-motion-y: calc(var(--spacing) * 2); }
  &[data-k-side="bottom"] { --k-tooltip-motion-y: calc(var(--spacing) * -2); }
  &[data-k-side="left"] { --k-tooltip-motion-x: calc(var(--spacing) * 2); }
  &[data-k-side="right"] { --k-tooltip-motion-x: calc(var(--spacing) * -2); }
  &[data-k-state="closing"] {
    animation-name: k-tooltip-out;
  }
  @media (prefers-reduced-motion: reduce) { animation: none; }
}
@keyframes k-tooltip-in {
  from { opacity: 0; transform: translate(var(--k-tooltip-motion-x), var(--k-tooltip-motion-y)) scale(0.95); }
  to { opacity: 1; transform: translate(0, 0) scale(1); }
}
@keyframes k-tooltip-out {
  from { opacity: 1; transform: scale(1); }
  to { opacity: 0; transform: scale(0.95); }
}

/* Mobile header motion; the open bar stays stable while the full menu fades in. */
@utility animate-header-menu {
  & .k-header-dropdown[open] > .k-header-submenu {
    animation: k-menu-in var(--k-motion-duration-sm) var(--ease-standard);
    transform-origin: top center;
  }
  & .k-header-dropdown[open] > .k-header-submenu[data-k-menu-state="closing"] {
    animation: k-menu-out var(--k-motion-duration-xs) var(--ease-standard) both;
  }
  & .k-header-dropdown:not([open]) > .k-header-submenu { animation: none; }
  & .k-header-dropdown-icon { transition: transform var(--k-motion-duration-sm) var(--ease-standard); }
  & .k-header-menu-icon svg > path {
    transition: transform var(--k-motion-duration-base) var(--ease-standard), opacity var(--k-motion-duration-sm) var(--ease-standard);
  }
  @media (width < 64rem) {
    &[data-k-header-state="open"] .k-header-panel {
      animation: k-header-menu-in var(--k-motion-duration-lg) var(--ease-standard) both;
    }
    &[data-k-header-state="closing"] .k-header-panel {
      animation: k-header-menu-out var(--k-motion-duration-base) var(--ease-standard) both;
    }
  }
  @media (prefers-reduced-motion: reduce) {
    & .k-header-dropdown[open] > .k-header-submenu,
    & .k-header-dropdown[open] > .k-header-submenu[data-k-menu-state="closing"] { animation: none; }
    & .k-header-menu-icon svg > path, & .k-header-dropdown-icon { transition: none; }
    &[data-k-header-state] .k-header-panel { animation: none; }
  }
}
@keyframes k-header-menu-in {
  from { opacity: 0; transform: translateY(8px); }
  to { opacity: 1; transform: translateY(0); }
}
@keyframes k-header-menu-out {
  from { opacity: 1; transform: translateY(0); }
  to { opacity: 0; transform: translateY(8px); }
}